People contain at least ten-fold more microbial than human cells. Recent data compel serious consideration of co-evolved microbial-host partnerships. We are, in fact, super-organisms and composites of many species. This nascent field of study has tremendous implications for human development, health, homeostasis, and disease, and the human enteric biomass represents the largest fraction of these organisms. For these reasons, we will present a course on the human intestinal microbiome in development, health and disease, in conjunction with the North American Society for Pediatric Gastroenterology Hepatology and Nutrition. The course will be open to a wide community of investigators in pediatrics, internal medicine, immunology, microbiology, dentistry, dermatology, and other fields, and feature lectures from a panel of pioneers in this discipline. Topics to be covered include the role of the intestinal microbiota in intestinal and extraintestinal inflammation, immune regulation, and the biology of probiotics. There will be particular emphasis on trainees, and preparation for careers in this multifacetted field. Biologic concepts related to the study of the intestinal microbiome will be emphasized. It is anticipated that this inaugural course on this topic will prompt a wide range of investigators to obtain training in techniques relevant to this field. Because microbiome studies are changing basic concepts of human biology so rapidly, and because so few trainees in this field are in the pipeline, it is critical that investigators learn about these emerging data, so that they can help convert this information into useful knowledge rapidly and efficiently, which is the goal of the course. [unreadable] [unreadable] [unreadable]